A flicker-noise-free DC-offset-free harmonic mixer in a CMOS process

A harmonic mixer for direct-conversion receivers is proposed and fabricated in a CMOS process. It is immune from both the flicker noise and self-mixing induced DC offset. Using the lateral bipolar transistor and the harmonic mixing technique, it achieves a +15 dB gain, 17.8 dB NF at 10 kHz frequency, -8.2 dBm IIP3, +44 dBm IIP2 and more than 30 dB DC offset suppression. It consumes 2.2 mW power at 3 V.